This invention relates to burglar alarms and more particularly to a door and window entry sensing system that instantly detects minute closure openings.
There has long been a need for a door and window alarm system that instantly detects the slightest opening of the door or window by means of super-sensitive door and window switches that automatically reset themselves. In systems having sirens and floodlights, provision should be made for shutting off the siren or alarm when only the floodlights are to be turned on. Also, when the floodlights and siren are on, low voltage power to the doors and window must be shut off. The siren should have control means enabling the siren to go on and off in preselected time cycles. Test switches should be provided for testing the alarm system without energizing the alarms and for testing the system in lieu of door and window switch actuation. There should be provision for opening of the doors for intended entry and opening the windows for ventilation without activating the alarm.
It is an object of the invention to provide an alarm system for sensing attempted entry through doors and windows by means of door and window switches that instantly detect even the slightest opening of the closure.
It is a further object of the invention to provide an alarm system of the above type having a siren and floodlight wherein the siren may be shut off when just floodlight use is desired.
A further object of the invention is to provide an alarm system of the above type wherein the low voltage power to the doors and windows is shut off when the alarm is activated.
A further object of the invention is to have the door and window switches automaticallv reset themselves after actuation.
A further object is to have the siren sound-off in preset on-off cycles.
A further object of the invention is to have the alarm automatically shut off after a preset time interval.
A further object of the invention is to provide means for easily deactivating the alarm system interiorly of the premises upon intentional opening of the door or window.
A further object of the invention is to provide means for testing components of the alarm system without activating the alarm.